Autism spectrum disorders (ASD) are defined by specific behavioral impairments in social interactions, verbal and non-verbal (gaze, face expression, gestures, prosody) communication, imaginative play, and by restricted and repetitive interests and behavior. Underlying these behaviors are deficits in social and non- social cognition and information processing. Interventions for autism have largely focused on the preschool years and behavioral methods. Few interventions are available for adults with ASD, and even fewer focus on the remediation of cognitive and social-emotional deficits in a way designed to improve complex adaptive behavior essential for success and achievement in adult life. As a consequence, many verbal adults with ASD experience substantial lifetime disability resulting in great personal and family suffering and great financial cost. In response to RFA-MH-09-021, "Novel Interventions for Neurodevelopmental Disorders," we propose the first step in adapting, piloting and preliminarily testing of the efficacy of Cognitive Enhancement Therapy (CET) for young transitional age high functioning adults with ASD to improve adaptive functioning and adult life achievement in this population. CET is a neurodevelopmentally-based, social-cognitive and neurocognitive rehabilitation program originally developed for schizophrenia that has demonstrated significant improvements in cognition and important functional outcomes. Many of the social, communication, and cognitive impairments experienced by persons with ASD (e.g., impaired theory of mind, deficient emotion perception, poor emotion regulation and expression, inflexibility, executive dysfunction) are also shared by individuals with schizophrenia. These impairments are directly targeted by CET, suggesting that CET may confer substantial benefits to verbal individuals with ASD who often do poorly as adults and for whom few interventions exist. This project will consist of two phases. In the first (R21) phase, adaptations to the CET treatment reflecting the uniqueness of autism will be made through the development of a supplement to the existing CET treatment manual. Clinical experts in autism and schizophrenia will collaborate to adapt CET, and then conduct an uncontrolled pilot study of these adaptations with 12 young adults with ASD to demonstrate feasibility, identify the need for additional adaptations, and provide an initial evaluation of the potential social-emotional and cognitive effects of the approach. In the second (R33) phase, a small-scale randomized trial with 55 young adults with ASD will be conducted to obtain initial efficacy data on a broad range of cognitive, functional, and neurobiological outcomes to support the feasibility of a larger and more definitive trial of CET for ASD. The proposed R21-R33 will result in the completion of the first rigorous clinical trial of a proven cognitive rehabilitation approach with verbal adults with ASD. If successful, this project will result in a major step forward in available interventions for adults with ASD, and have implications for both younger individuals with autism and other neurodevelopmental disorders that share similar cognitive, affective and social impairments.